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Why is it that the turbines can be turned into a bridge and a playground but can't continue to be used? What is the failure mode for these things?
Spinning turbine blades are under significant mechanical stress. Individual blades are getting as tall as a 30 story buildings, but they rotate so you need to support all that weight from one end. Further, the tips are spinning at 100+MPH constantly so dust in the air is eroding the surface.

On top of this weight savings are a major goal so their designed to just barely work for a given lifespan. So, blades that where pulled from a working turbine are still really strong, they are simply more likely to fail at some unknown point in the future.

PS: Turbines from 20+ years ago are much smaller, but faced similar issues. For scale compare the turbine blade with cars in this shot and think this thing is rotating: https://www.technology.org/2018/03/23/here-is-the-worlds-lar...

Are there any recorded instances of this happening? A turbine falling apart when taken past its design lifetime?
About 3,800 wind turbine blades fail per year, according to an insurer.[1] About 0.5% per year. A detailed analysis of blade failure modes: [2] There's an industry devoted to blade repair.[3] What they do looks a lot like body work for carbon-fiber aircraft, except that it's done in midair.

Transmissions and bearings are more of a problem. "Turbine gearboxes are typically given a design life of 20 years, but few make it past the 10-year mark."[4]

[1] https://www.enr.com/articles/42352-are-four-wind-turbine-fai... [2] https://backend.orbit.dtu.dk/ws/portalfiles/portal/118222161... [3] http://fairwindres.com/wind-industry-maintenance/blade-repai... [4] https://www.windpowerengineering.com/wind-turbine-gearboxes-...

> Turbine gearboxes are typically given a design life of 20 years, but few make it past the 10-year mark.

That's why the biggest and best are direct drive.

It is all about trying to avoid having a broken/breaking wind turbine. A spinning wind turbine falling apart is no fun for bystanders involved [0].

[0]: https://www.youtube.com/watch?v=7nSB1SdVHqQ

That's a towerstrike and overspeeding, nothing to do with the blades being worn out.
I.e. cumulative fatigue damage from the constant flexing of the blades.
It's a 30 storey fiberglass building spinning at speed. The stress is high and the material fatigues over time. Eventually it will crack, a stress concentration will occur and the crack will propagate somewhere important and it will fail completely.

Now take that same material and give it a much shorter span/length, and a much lower loading, and fatigue becomes less of an issue.

I'm not sure what bridge they're talking about in specific but I don't see why they couldn't be beams for a pedestrian bridge providing. I bet the manufacturer has a lot of testing data too.

Cumulative fatigue damage goes up as the cube of the stress, if I recall correctly.
Wouldn't that imply that a modest over-design could significantly improve blade life?
They are designed to be constructable, affordable, reliable, and somewhat maintainable (as maintainable as a giant windmill full of electricity generating equipment can be I guess).

If it was easy and cheap to make them last longer someone would do so and win the market.

The failure mode is not as other posters have said mechanical, but is in fact usually a business decision. Plenty are lasting much longer than 25 years.

Many wind turbines were built with subsidies to run them for 25 years. As soon as that time is up, they may no longer be worth running, especially since in many places wholesale power costs have dropped due to other subsidised wind and solar.

Also, finding sites to build wind turbines is getting tricky - you need good wind, no complaining neighbours, good road and crane access, and a good grid connection. That usually makes existing wind turbine sites excellent candidates for building bigger better turbines which are 10x the size.

I was not suggesting me mechanical stress was the only issue, rather blades that needed to be able to withstand much larger stresses as part of a wind turbine than as playground equipment or as bridge components. However, it does directly cause problems. “The main reason to create fatigue in the wind turbine blades is cyclic loads. Variation of wind speed, annual gust, rotation of rotor, and variation of weight vector direction toward the local position of the blade [17] are the production sources of the cyclic loads.“ https://www.intechopen.com/books/wind-turbines-design-contro...

Study of fatigue damage in wind turbine blades “The inspection of damages detected in some blades of 300 kW wind turbines revealed that the nature of these damages was probably due to a fatigue mechanism. The causes that had originated the failure (superficial cracks, geometric concentrator, abrupt change of thickness) have been studied, verifying, by means of the simplified evaluation procedure of fatigue life of the “Germanischer Lloyd” (GL) standard, that these causes can explain the failure detected in the period of time in which it happened.“

https://www.sciencedirect.com/science/article/abs/pii/S13506...

That seems like a relatively old study now. I think blade design and manufacture has developed rapidly. Here is a short piece on the testing of much larger modern blades designed to last at least 25 years offshore [1]

[1] https://www.youtube.com/watch?v=5m-jwwM3qRs

This article is about blades that are actually 25 years old and being replaced. The video is testing is to ensure new blades can handle both peak stresses in the static test and less stressful cyclical loading for 25 years. So, 25 years from now those blades will also reach the end of their service life and need to be replaced.

That said monitoring and inspection can maximize the lifespan of individual turbines even if nobody is aiming for 50+ year service life.

I'm not suggesting they could be expected to last beyond their design. Just when this is the state of blades being built in unprecedented number today, a twelve year old review of much smaller ones made 35 years ago could easily be largely outdated.
If I recall correctly, fiberglass is a pretty decent heat insulator. Wouldn't be possible to cut those blades into tiles, then reshape them to be perfectly flat and use them as heat insulation panels in non critical industrial applications?
If I recall correctly, fiberglass is a pretty decent heat insulator. Wouldn't be possible to cut those blades into tiles

The physics of insulators, like fiberglass batting. Basically, it works the same way as down feathers or fur. The material traps air into many, many somewhat separate pockets. This interrupts convective flows, which drastically slows down the rate at which heat can move through air. Since air is the opposite of dense, not much heat can be transmitted through air which does not move.

Fiberglass tiles aren't going to have the same insulating property, just because they're also fiberglass.

What about crushing them and then kind of shredding it into a mulch to create the pockets?
They're fiberglass composite, so fiberglass in epoxy, unlike fiberglass insulation.
We do need to find solutions for blade-waste. Ideally it would find its way into new blades.

On other hand, how does blade-waste compare to energy- and non-energy- waste sources? Until that solution arrives:

" municipal and commercial dumps will take most of the waste, which the American Wind Energy Association in Washington says is safest and cheapest. 'Wind turbine blades at the end of their operational life are landfill-safe...' [The group] pointed to an Electric Power Research Institute study that estimates all blade waste through 2050 would equal roughly .015% of all the municipal solid waste going to landfills in 2015 alone."[0]

[0]https://www.bloomberg.com/news/features/2020-02-05/wind-turb...

> We do need to find solutions for blade-waste.

Why? We're in no danger of running out of space, and they're not toxic.

Yeah, I mean, all other things being equal it's better to find efficiencies where possible and not just throw things away needlessly. Folks like to laugh at it, but plastics manufacturing for one-use items like bags and straws has real externalities that aren't borne by the cost of manufacture.

But in this particular situation: a quarter-century-old turbine blade has paid for itself so many times over already that this is just not where we need to be spending out time worrying about efficiencies. Even if we just bury the things, wind power remains (by far!) the most environmentally beneficial choice for almost all electrical markets.

> has real externalities

If they're blowing around in the wind or dumped in the waterways, sure. If they're buried, none I've heard of.

I agree. I'd even say that burying plastic is a form of carbon sequestering and therefore has some positive impact. However, I think the problem with burying plastic is the stuff that leaches out.

See https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5373626 for example.

I wonder if double-bagging your garbage would help or hurt? It would be ironic if a good solution turned out to be more plastic packaging.
This post is entirely without merit and is false. No wind turbine has ever paid for itself cradle to grave.

How is this allowed to stand?

Why do you prefer wind to solar?
'All electricity markets' is probably a bit overblown. For Europe north of the alps, there's not that much sun, but often plenty of wind.
It's cheaper and faster to build out, lasts longer once installed, is usually easier to find sites for, and can be built with almost completely local manufacturing and labor. There's nothing wrong with solar, but wind is better from a "where should the subsidy dollars be spent" perspective.
Even better: don't spend any subsidy dollars at all. Use a carbon tax to turn climate policy into a money spinner instead of a money sink, and let the market figure out how to generate power.

(In political practice, it seems easier to throw around subsidy dollars, alas.)

It’s mostly fiberglass.

I think this entire article lost sight of the relevant scale, because blades are big compared to humans and energy (and the physical waste of displaced energy sources) is invisible.

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Sailing yachts too. Millions of affordable fiberglass yachts made since the 70's are now reaching the end of their lives. In the past abandoned wooden boats just rotted away. But the fiberglass hulks stick around. It's a coming problem.
Nothing escapes entropy, but if you multiply the rate at which everything naturally decays with the sheer volume of things that exist and will one day need to be replaced, we're going to bankrupt the planet of its resources.

I wish more things were made to last. Imagine working in a 5000 year old skyscraper that's as good as the day it opened, or driving a 500 year old car that's as reliable as the day you purchased it.

Humanity's going to last a long, long time. Hopefully.

At least resources like wood and water are renewable. But oil and metal aren't. When we run out of oil, we can kiss plastics and cosmetics goodbye. As for metals, recycling scrap metal and asteroid mining are our only long term options.

>Imagine working in a 5000 year old skyscraper...

Living in Europe and having ample opportunity to visit them, I'm always fascinated by the old cathedrals that just stand around in our city centers. I almost can't believe how people hundreds of years ago managed to erect these structures. And not only that but the level of detail and craftmanship that went into all of its components is mind-boggling. To me it also signifies a connection to previous generations which you don't often get anywhere else. Of course they are not nearly 5.000 years old, but it just sprang to my mind when I read this line.

Also living in Europe, I find myself in awe of this fact quite often. There was a time when 'high technology' meant, knowing how to cut stone in such a way that it could be transported and assembled by an illiterate mob into a vast cathedral.

And then, there are the aquaducts and water mills scattered all over the region (Austria). What an astonishing thing to see, still in operation, hundreds of years after they were built, water wheels pulling water up into the castle ..

> illiterate

That doesn't mean they were stupid or didn't have intimate knowledge of their craft.

In those days, models were built by the designers which were then given to the craftsmen to build. There's a museum in England which houses the ship models built by the naval architects to give to the ship builders. The models are exquisite.

That's right, it simply means "cannot read and write" - but that's my point .. even in spite of the fact that the end assembly process was being done by folks who could not read/write (most of the time) they were still able to assemble these extraordinary structures using the technology available to them.

And the technology of communicating to these craftsmen and artisans is another subject itself .. here in Vienna, we also have museums devoted to such things. I find it really fascinating personally.

>here in Vienna, we also have museums devoted to such things

Can you provide a link of which museum you're talking about specifically?

Just in case someone reading this happens to be living in Vienna... ;)

Technical Museum! (http://technischesmuseum.at)
Ha, funnily enough I was just thinking about looking up a technical museum in Vienna 2 days ago. Thank you!

I'm also a big fan of the Deutsches Museum in Munich:

https://www.deutsches-museum.de

Yes that is an awesome museum, too! Be sure you make the effort to find the computing-history section - there are some awesome things to see there, such as the original Z4 from Konrad Zuse, and a replica of his Z3 too ..

A bummer the Space pavilion is closed at the moment though. Definitely better to plan a visit to Munich when that re-opens again.

The craziest part is these were built over very long periods of time spanning multiple generations. Inter-generational cooperation is just something I can't imagine happening today.
Köln cathederal was started in 1248 and finished in 1880 (albeit with a bit of a gap in the middle).
The Sagrada Familia was started in 1882 and should be finished in 2026. That's a much shorter span, but it's entirely within the modern era.
A number of these older structures also have modern reinforcements added to keep them from collapsing.

People love these old structures (as do I) and non-trivial effort is put into protecting and maintaining them.

For a famous example, there's the leaning tower of Pizza.

We could make structures that last essentially forever today. But it's often not the right economic trade-off.

One simple example: reinforced concrete usually decays after a few decades. Without the rebars inside, we could make our concrete last much longer. But we'd lose out on the magic engineering properties of reinforced concrete.

Rome is even more impressive - 2000 years old buildings. Pantheon is just huge!
And the Pantheon still has the world’s largest cupola inside. We still don’t understand how to build them that big, despite 2000+ years of studying that sucker.
We know exactly how to build them that big, but choose not to because we have better materials and better techniques. That cupola was created because the builders were too ignorant to figure out a better way to enclose the space, with modern steel it is trivial to create a building that encloses the entirety of the Parthenon.
I was planning on finally visiting Rome this year :)

Everyone who's already been tells me it's really impressive

>driving a 500 year old car that's as reliable as the day you purchased it

Telemetry would be the first thing on the backports list before the car is deemed roadworthy again.

I don't believe that, because otherwise companies like them https://www.fj.co/ wouldn't have a business case.

There are also many others in that space fixing old timers, or 'new' old timers, say from the 80ies or 90ies. Can all be had without telemetry. Are there regions who allow absolutely NO EXCEPTIONS to 'grandfathered in' cars?

Wouldn't that be so totalitarian?

> [...], we're going to bankrupt the planet of its resources.

Do you have an idea how big a ball of matter we are sitting on?

> At least resources like wood and water are renewable. But oil and metal aren't. When we run out of oil, we can kiss plastics and cosmetics goodbye.

Carbon and hydrogen and oxygen are plentiful. Oil is just convenient because it already combines them and also comes with a lot of easily usable energy.

But if you are willing to (or forced to), you can make plastics (or even oil or fuel) from scratch, you 'just' need to supply your own external energy. Nuclear or solar or wind etc will do just fine for that.

As an intermediate step, you can use coal as your raw material. Not as convenient as oil, but we have more reserves of it around the globe.

There was a story here on HN just yesterday about Edison's experiments with goldenrods to create rubber.

His variant of goldenrods were about 12% latex after some selective breeding.

I'd be curious what kind of plants we could engineer today to make rubber with. There's tons of stuff out there and yes we don't necessarily need oil or other resources if push comes to shove.

Yes. Though do keep in mind that having cheap oil is infinitely more convenient than the substitutes we are talking about.

The world won't end if we ran out of (cheap) oil in the next few years. But productivity would take a bit of a hit for at least a while.

> In the past abandoned wooden boats just rotted away. But the fiberglass hulks stick around. It's a coming problem.

Wait, doesn't rotting mean it releases the CO2 stored in the wood? I would says that's an issue more than something inert.

Why can't we just use the existing hulls to build more ships?
New fiberglass is shiny and smooth.

Old fiberglass is full of cracks, scrapes, and holes.

It's repairable, but the repair is highly labour intensive, whereas making a new boat uses less labour.

Also, any repaired fiberglass item will always have a worse strength to weight ratio than a new item - you simply can't efficiently bond new to old fiberglass in a strong way.

Is it a bigger problem than rocks?
Fiberglass is pretty inert, right? It's also used for boat hulls. I wonder if turbine blades could be cut up and used for artificial reef construction the way decommissioned ships sometimes are. But perhaps the blades are lighter than water.
As a diver, I have to say, artificial reef isn’t quite what you think. We dive wrecks all the time that are 60-130’ down and have been there for 70-100 years and barely have any coral, certainly not like the massive walls of coral elsewhere in the same islands.

Some of it has to do with the depth: most life is in the 0-40’ zone. And the oxygen drops off quite a bit, which inhibits oxidation (rust). There’s another wreck we dive at 40’ that’s barely recognizable due to corrosion and life. There’s an area that has coke bottles from 1945 (the glass is date-stamped) and they barely have anything growing on them.

If you dump fiberglass in shallow water, people are going to be pissed. If you dump fiberglass in deep water, it will likely not decompose for millennia. But it also won’t be a Mecca for perch and sharks like some make them out to be.

Fiberglass would break down and release microplastics, though, so it is not as environmentally friendly as a sunk metal hull.
You can't work fiberglass like metal. It can't be welded and it fractures before it bends. That's partly why fiberglass parts in complex shapes tend to be expensive - they must be shaped at the time of manufacture before they cure. Fiberglass is a fiber reinforced resin which is typically built by laying down thin fibrous sheets in molds and "painting" them with liquid resin. Also labor intensive and hard to automate.
This is a non-issue. When we have enough of them for them to be readily available in large quantities we will find uses for them. Being slow to degrade when exposed to the elements makes them (or strips/panels cut out of them) suitable for all sorts of construction uses.
I wonder if they could be used to build a fence. Or maybe a wall?
I'm not sure why you're getting downvoted but I think cross sectional cuts of turbine blade filled with dirt or concrete (as budget allows) would make for great retaining walls or erosion barriers.
Well, in a sense it becomes a non-issues when someone takes it serious as an issue and finds economic uses.

Of course, that doesn't mean the whole of society has to worry about it.

And in the worst case, we can just dump them on landfills until we know what to do with them.

> It stretches a hundred metres from a bend in the North Platte River in Casper, Wyoming.

100m? For real?

> Burying them doesn't sound very green.

Why do I care if something doesn't sounds green? Tell me an actual consequence.

Clickbait FUD. Here we go again, the BBC taking up side of the fossil fuel industry to manufacturer consent with a propaganda FUD piece against renewables or stir up some phony outrage to sell ads. No renewable energy source is perfect, but it's better than "clean coal" or tarsands. Hand-wringing about the least bad option doesn't do anything constructive, it just demonstrates dilettante ignorance and snobbery to find minutiae to complain about when the climate change emergency, antibiotic/antimycotic resistances and renewed threats of nuclear war are just some of the numerous Swords of Damocles over us right now. Instead of informing, the majority of the corporate mainstream media choose bread and circuses over committing journalism. Journalism is a crime now, my bad! #FreeAssange et. al.
Maybe give them to association for upcycling or non industrial dismantling ?